Radio receiving apparatus



Jan. 5 1926.

I L. Q. SLOCUMB RADIO RECEIVING APPARATUS- -Fi1ed Jan. 2, 1924 2 s t -sht 1 Jan, 5 1926.

L. Q. SLOCUMB RADIO RECEIVING APPARATUS Filed Jan. 2. 1924 2Sheets-Sheet 2 lib reamed Jan. 5, 1926.

UNITED STATES LLOYD Q. SLOCUMB, OI FERGUSON, MISSOURI.

RADIO RECEIVING APPARATUfi.

Application filed January 2, 18%. serial No. 683,887.

To all whom it may concern:

Be it known that I, LLOYD Q. SLocUMB, a citizen of the United States,and a resident of Ferguson, St. Louis County, Missouri,

have invented an Improvement in Radio" Receiving Ap aratus, of which thefollowing is a speci cation.

This invention relates to radio receiving apparatus, and with regard tocertain more specific features, to apparatus for amateur use.

Among the several objects of the invention may be noted the provision ofan accurate and simplified control; and the provision of a simple andinexpensive device, readily installed and calibrated. Other objects willbe in part obvious and in part pointed out hereinafter.

The invention accordingly comprises the features of construction,combinations of elements, and arrangements of parts, which areexemplified in the constructions herein: after described and the scopeof the application of which will be indicated in the following claims.

In the accompanying drawings, in which are'illustrated one or more ofvarious possible embodiments of this invention,

Fig. 1 is a plan;

Fig. 2 is a vertical transverse section on the lme 22 of Fig. 1; 1

Fig. 3 is a, fragmentary face view coil;

Fig. at is a diagram;

Fig. 5 is a diagram of a modification;

Fig. 6 is a plan of a modification; and

Fi 7 is a verticaltransverse section on the line 7-7 of Fig. 6.

Similar reference characters indicate correspondin 7 parts throughoutthe several of'a -views of t e drawings.

Referring now more particularly to Figs. 1 to 4 of theaccompanyingdrawings, there is illustrated at 1 a top panel 1 enclosinga box 3. The panel is slotted as at 5 to re ceive a vertical shaft 7extending from the condenser '8 11 through the slot 5, and adapted toreceive a handle such as the Mob 1?. bearing a scale 13. I

its will be seen hereinafter, this scale may ordinariiy be calibrated bywave lengths or names of broadcasting stations.

The condenser 9, which is a variable the circuit comprises fined plates15 and movahle plates 17, and is mounted slide SS has preferably fiftyturns in it.

whole, in guides 19 secured to the top panel 1 by suitable means, suchas screws 21 r (Fig. 2

Rotation of the knob 11 causes rotation of the movable plates 17 withrespect to the fixed plates,15, thereby varying the capacity of thecondenser.

Movement of the knob 11 parallel to the panel, throughout the range oftravel permitted by the slot 5, causes the condenser to move bodily.Thismovementdoes not affect the internal capacity of the condenser as aninstrument,- but is primarily for the purpose of varying the relativeposition of two inductance coils 23, -25, constituting another type ofvariable of the circuit.

The coil 23 (Figs. 1 and 3) is fixed in position. This coil comprises aspider 27 of insulating material, on which is wound a grid coil SS, uponthe outside of which is wound an aerial ground coil AG. The latter coilhas several ta s. A preferred arrangement of taps is, t ree taps on thefirst turn of the aerial ground coil, then a single turn and a tap andthen a tap every two turns for a total of sixteen turns. The coil coilsare preferably Number 24 double cotton covered copper wire.

The movable coil 25 (Fig. 1) may be termed the plate coil or ticklercoil. This coil is preferably of the same construction as the coil 23,and has preferably about forty turns of Number 24 double cottoncoveredcopper wire.

The two coils 23, 25 are both horizontal and are spaced about an inchand a quarter apart. The fined coil 23 is secured to the underside ofthe panel 1. The movable coil 25 is ivotally mounted at 29 and isadapted to e rotated about said axis 29, in a horizontal plane, from thelower dotted position in l, to the upper dotted position in said figure,so as tovary the interaction between said coil and the first coil 23.Such rotation oi the movable coil 25 is effected through a link 31pivotally con nected to a lever 33 which in turn is pivotally mountedupon the condenser shaft 7 lever 33 is preferably of insulatingmaterial.

ovement oi? the knob 1.1 and shaft 7 tod rigl'it (Fig. 1} thus causesmoveof the c 25 from its lower dotte (Fig. i

Both

its upper dotted I tion (Fig. 1) thereby bringing the coils 23 and 25into closer proximity, thereby.

alternating the intensity of the current in the telephones hereinafterdescribed.

The grid condenser is connected to the inner end (Fig. 3) of the coilSS.

Thus by operating the knob 11, the intensity may be adjusted bylongitudinal movement of the rod, and the wave length may be adjusted byrotation of the knob. A second knob 35 is shown in Fig. 1, and isadapted to control the rheostat 37 '(Fig. 4) to vary the intensity ofcurrent in the filament 39 of the tube 41 (Fig. 4).

On one side of the box 3 are shown (Fig. 1) binding posts 43 for Bbattery and binding posts 45 for A battery, 47 for ground,

and 49 for taps of the aerial ground coil.

The aerial 53 is connected to one oranother of the taps 49- as may bedesired, de-

ending upon the number of turns desired or the aerial ground circuit AGin the coil 23. Taps additional to those shown at 49 maybe provided asrequired, in order to take care of the desired number of taps from theaerial ground coil.

Binding posts 51 are shown on the other side of the box, for thetelephone or other translating device circuit.

In Fig. 4 is illustrated diagrammatically a preferred system of wiring.The aerial .53 runs to the aerial ta .A (which is some one of theposts49 of ig. 1) extending to the aerial ground coil AG. The other endg f the coil is grounded as indicated in This aerial ground coil isclose-coupled, as indicated in 'Fi 3, to the grid coil SS. The rid coilSS has bridged across it the varia 1e condenser '9' Fig. 2), and is inseries with a grid lea 55 bridged b a grid condenser 57, the circuitthen leading to the grid 59 of the tube 41. v

The filament 39 of said tube 41 is connected, through the rheostat 37,to the negative side of the A battery A, the positive side of which isconnected to the lower lead (Fi 4) from the id coil. The latter lea isconnected to t e filament 39 and to the negative side of the B batteryB.- The negativevside oi the B battery B is connected to the translatindevice illustrated conventionally as a hea set 61, the circuit thenextending through the movable coil 25 and thence to the plate 63 of thetube 41.

In the modification illustrated in Fig. 5, the B battery is omitted, anda coil 65 of about one hundred turns of Number 24 double cotton coveredco per' wire is inserted in the translating evice circuit that includesthe movable coil 25. The circuit is otherwise the same as in Fig. 4.

In Figs. 6 and 7 is illustrated a modified control for the movable coil25. In this embodiment of the invention the fixed coil (wave lengths an23 is vertical, and the movable coil 25 swings from a vertical positionabout one and one-quarter inches away from the fixed coil 23, clockwise(Fig. 7) to a position at an angle to the vertical, as indicated indotted lines in Fig. 7. This elevated position of the movable coil isalso indicated in Fig. 6.

The lifting of the coil is effected by the longitudinal movement of theknob 11 in the slot 5 in the anel 1-. For this purpose, a piece of cord6 is connected to the lower end of the movable coil 25 and passesthrough an eye 69 and thence to the end of a lever 71 pivoted to thepanel at 73 and at its other end pivotally connected to a link 75 whichis pivotally secured to the condenser 9.

In this modification, as in 'theconstruction first above described, theextent of cooperation between the fixed and movable coils, and thereforethe intensity of current in the translating device 61, is varied bymoving the knob 11 rectilinearly in the slot 5, whereas rotation of thesame knob serves to tune the apparatus to the desired wave length.

For calibration urposes, the scale indicia d/or names of broadcastingstations) are, preferabl on a scale. disc 13 which is secured to the nob11, and the knob is detachably connected to the shaft 7 by means ofa'set screw 14 (Fig. 2). In the initial tuning of the set, the operatortunes the set to receive some known broadcasti'iig station, the name orwave length of'which is on the dial. Then, if in the position forreceiving said station, the name or wave length of that station is notat the station line 77 on the panel, the operator loosens the set screw14, and, without rotat- I ing the shaft 7, rotates the knob 11 until thename or wave length of said station is o posite the station line 77 onthe panel.

e then tightens the set screw. The appardus is now calibrated for all ofthe stations on the dial. Y

In view of the above it will be seen that the several objects 01- theinvention are achieved and other advantageous results attained. I Asmany changes could be made in carrying out the above constructionswithout departing from the scope of the invention, it is intended thatall matter contained in the above description or shown in theaccompanying drawings shall be interpreted as illustrative and not in alimiting sense.

I claim:

1. A compound radio adjustment comprising a fixed coil, a movable coilpositioned in operative relation thereto, means movable substantiallyparallel to a panel for mountin thereof adapted to move said movable 00'with respect to said fixed coil, a

.Ja-riable condenser, said'means being mov- I first means affecting onlythe position of on which said handle is said movable coil.

2. In a radio receiving set, a compound adjustment for variables of acircuit comprising a single handle, a panel, means for mounting saidhandle on said panel for rotation to vary one of said variables, and forsimultaneous movement in a predetermined path to vary another of saidvariables, said handle being adapted to be moved in either of said waysindependently of the other movement.

3. In a radio receiving set a compound adjustment for two difierentvariables of a circuit governed by different instruments comprising asingle handle, a panel, means for mounting said handle on said panel forrotation and simultaneous movement-in a predetermined path arallel tosaid panel, said handle being a apted to be moved in either of said waysindependently of the other movement and, when desired, .without saidother movement.

4. In a radio receiving set, a compound adjustment for variables of thecircuit, said adjustment comprising a handle, a support mounted forrotation and simultaneously for movement in another path, a variablecondenser having an element secured to the handle for movement therewithin said path and having an element rotatable with the handle wherebyrotation of the handle varies the capacity of said condenser; asecondary coil and a feed-back coil, one movable relatively to theother, and means whereby the movement 0 said handle in said path effectsrelative movement of said coils 5. A compound adjustment for two radioadjustments comprising a rotatably operable device slidably mounted,said device varying the capacity of a variable condenser when it isrotated, two coupled coils, means whereby when said device is slid thecoupling between the coils will be varied, said device being capable ofsimultaneous but independent rotatable and sliding movement, bothmovements taking lace substantially parallel to a panel on which theadjustment is mounted.

6. In a radio receiving set, a tuned secondary coil, a feed-back coil,one of said coils being movable relatively to the other to effect avariable coupling between them, a variable condenser adapted to bevaried by rotation of one of 1ts elements, and adapted to move bodily asa whole in a predetermined path, a control movable with said condenserin said path and connected to said movable coil whereby movement of saidcontrol in said path varies the relative position of said coils, saidcontrol being also connected to the rotatable part of the condenserwhereby rotation of said control varies the capacity of said condenser,said rotation and said other movement of said control being capable ofbeing effected simultaneously. v

7. In a radio receiving set, a tuned secondary .coil, a feed-back coilvariably coupled thereto, one of said coils being movable relatively tothe "other, a tuning element, a support on which said element ismounted, a connection between said element and said movable coil wherebybodily movement of said element varies the relative position of saidcoils, and a control for adjusting said element and for movlng saidelement bodily, said adjusting movement 'and bodily movement beingcapable of f. being effected simultaneously.

In testimony whereof, I have signed my name to this specification this31st day of December, 1923.

' LLOYD Q. SLOCUMB.

